xref: /netbsd-src/lib/libkvm/kvm_x86_64.c (revision c2f76ff004a2cb67efe5b12d97bd3ef7fe89e18d)
1 /*	$NetBSD: kvm_x86_64.c,v 1.8 2010/09/20 23:23:16 jym Exp $	*/
2 
3 /*-
4  * Copyright (c) 1989, 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software developed by the Computer Systems
8  * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
9  * BG 91-66 and contributed to Berkeley.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #if defined(LIBC_SCCS) && !defined(lint)
38 #if 0
39 static char sccsid[] = "@(#)kvm_hp300.c	8.1 (Berkeley) 6/4/93";
40 #else
41 __RCSID("$NetBSD: kvm_x86_64.c,v 1.8 2010/09/20 23:23:16 jym Exp $");
42 #endif
43 #endif /* LIBC_SCCS and not lint */
44 
45 /*
46  * x86-64 machine dependent routines for kvm.
47  */
48 
49 #include <sys/param.h>
50 #include <sys/user.h>
51 #include <sys/proc.h>
52 #include <sys/stat.h>
53 #include <sys/kcore.h>
54 #include <sys/types.h>
55 
56 #include <stdlib.h>
57 #include <unistd.h>
58 #include <nlist.h>
59 #include <kvm.h>
60 
61 #include <uvm/uvm_extern.h>
62 
63 #include <limits.h>
64 #include <db.h>
65 
66 #include "kvm_private.h"
67 
68 #include <machine/kcore.h>
69 #include <machine/pmap.h>
70 #include <machine/pte.h>
71 #include <machine/vmparam.h>
72 
73 void
74 _kvm_freevtop(kvm_t *kd)
75 {
76 
77 	/* Not actually used for anything right now, but safe. */
78 	if (kd->vmst != 0)
79 		free(kd->vmst);
80 }
81 
82 /*ARGSUSED*/
83 int
84 _kvm_initvtop(kvm_t *kd)
85 {
86 
87 	return (0);
88 }
89 
90 /*
91  * Translate a kernel virtual address to a physical address.
92  */
93 int
94 _kvm_kvatop(kvm_t *kd, vaddr_t va, paddr_t *pa)
95 {
96 	cpu_kcore_hdr_t *cpu_kh;
97 	u_long page_off;
98 	pd_entry_t pde;
99 	pt_entry_t pte;
100 	paddr_t pde_pa, pte_pa;
101 
102 	if (ISALIVE(kd)) {
103 		_kvm_err(kd, 0, "vatop called in live kernel!");
104 		return (0);
105 	}
106 
107 	cpu_kh = kd->cpu_data;
108 	page_off = va & PGOFSET;
109 
110 	/*
111 	 * Find and read all entries to get to the pa.
112 	 */
113 
114 	/*
115 	 * Level 4.
116 	 */
117 	pde_pa = cpu_kh->ptdpaddr + (pl4_pi(va) * sizeof(pd_entry_t));
118 	if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde),
119 	    _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
120 		_kvm_syserr(kd, 0, "could not read PT level 4 entry");
121 		goto lose;
122 	}
123 	if ((pde & PG_V) == 0) {
124 		_kvm_err(kd, 0, "invalid translation (invalid level 4 PDE)");
125 		goto lose;
126 	}
127 
128 	/*
129 	 * Level 3.
130 	 */
131 	pde_pa = (pde & PG_FRAME) + (pl3_pi(va) * sizeof(pd_entry_t));
132 	if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde),
133 	    _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
134 		_kvm_syserr(kd, 0, "could not read PT level 3 entry");
135 		goto lose;
136 	}
137 	if ((pde & PG_V) == 0) {
138 		_kvm_err(kd, 0, "invalid translation (invalid level 3 PDE)");
139 		goto lose;
140 	}
141 
142 	/*
143 	 * Level 2.
144 	 */
145 	pde_pa = (pde & PG_FRAME) + (pl2_pi(va) * sizeof(pd_entry_t));
146 	if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde),
147 	    _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
148 		_kvm_syserr(kd, 0, "could not read PT level 2 entry");
149 		goto lose;
150 	}
151 	if ((pde & PG_V) == 0) {
152 		_kvm_err(kd, 0, "invalid translation (invalid level 2 PDE)");
153 		goto lose;
154 	}
155 
156 
157 	/*
158 	 * Level 1.
159 	 */
160 	pte_pa = (pde & PG_FRAME) + (pl1_pi(va) * sizeof(pt_entry_t));
161 	if (_kvm_pread(kd, kd->pmfd, (void *) &pte, sizeof(pte),
162 	    _kvm_pa2off(kd, pte_pa)) != sizeof(pte)) {
163 		_kvm_syserr(kd, 0, "could not read PTE");
164 		goto lose;
165 	}
166 	/*
167 	 * Validate the PTE and return the physical address.
168 	 */
169 	if ((pte & PG_V) == 0) {
170 		_kvm_err(kd, 0, "invalid translation (invalid PTE)");
171 		goto lose;
172 	}
173 	*pa = (pte & PG_FRAME) + page_off;
174 	return (int)(NBPG - page_off);
175 
176  lose:
177 	*pa = (u_long)~0L;
178 	return (0);
179 }
180 
181 /*
182  * Translate a physical address to a file-offset in the crash dump.
183  */
184 off_t
185 _kvm_pa2off(kvm_t *kd, paddr_t pa)
186 {
187 	cpu_kcore_hdr_t *cpu_kh;
188 	phys_ram_seg_t *ramsegs;
189 	off_t off;
190 	int i;
191 
192 	cpu_kh = kd->cpu_data;
193 	ramsegs = (void *)((char *)(void *)cpu_kh + ALIGN(sizeof *cpu_kh));
194 
195 	off = 0;
196 	for (i = 0; i < cpu_kh->nmemsegs; i++) {
197 		if (pa >= ramsegs[i].start &&
198 		    (pa - ramsegs[i].start) < ramsegs[i].size) {
199 			off += (pa - ramsegs[i].start);
200 			break;
201 		}
202 		off += ramsegs[i].size;
203 	}
204 
205 	return (kd->dump_off + off);
206 }
207 
208 /*
209  * Machine-dependent initialization for ALL open kvm descriptors,
210  * not just those for a kernel crash dump.  Some architectures
211  * have to deal with these NOT being constants!  (i.e. m68k)
212  */
213 int
214 _kvm_mdopen(kvm_t *kd)
215 {
216 
217 	kd->usrstack = USRSTACK;
218 	kd->min_uva = VM_MIN_ADDRESS;
219 	kd->max_uva = VM_MAXUSER_ADDRESS;
220 
221 	return (0);
222 }
223